A cyst manifests as a small bump under your cat's skin. Cysts can be caused by an infection, a clogged duct or a foreign object, which causes a reaction in your cat’s body. Your cat’s body forms a sac of tissue with a lining that secretes the cyst’s filling. Cysts may be filled with pus, fluid, semi-fluid/solid tissue or dead cells and are usually harmless and do not require treatment. Most cysts will either absorb back into the body or remain benign and unchanged. However, if they are the result of an infection, interfere with your cat's movement, or cause pain or discomfort due to their location, they must be removed or drained. If your veterinarian opts to drain the cyst rather than remove it surgically, it may be drained by inserting a needle and draining the cyst or, if your veterinarian feels that it warrants it, an open drainage of the cyst may be performed. 

Open drainage is an option chosen when an acute or chronic cyst occurs that does not respond to traditional treatment methods. Open drainage of a cyst involves making a surgical incision and then inserting a drain, a small surgical rubber tube, into the wound, suturing, and leaving in place, so that fluid can continually drain over a period of time. This method gives the wound a chance to clear itself of all abnormal fluid and tissue, which will allow your cat’s body to then heal properly without abnormal tissues present. A veterinarian will be able to advise you on the most appropriate form of treatment for a cyst that has become problematic.

If your cat requires open drainage of a cyst, they will usually need to be put under anesthetic. Prior to putting your cat under anesthesia your vet will want to do a physical examination on your cat to ensure there are no underlying conditions, like systemic infection, or respiratory disorders, that would make the use of anesthetic problematic. You will also be asked to have your cat fast from food prior to administration of anesthetic to decrease the risk of vomiting and aspirating vomit while under anesthetic. If there is any question as to the nature of the cyst your veterinarian may want to take a biopsy of the cyst tissue, prior to any procedure, to determine if cancerous cells are present.

To perform an open drainage of a cyst, your veterinarian will use general anesthetic. The area where the drain is to be inserted will be shaved and cleaned antiseptically. An incision will be made in the cyst and excess fluid allowed to drain from the wound. If necessary, fluid and tissue may be “pumped” out, a Penrose drain will then be placed into the incision and sutured in place to allow for continuous drainage of the cyst. The drain may remain in place for several days or weeks depending on how drainage and healing progresses. The drain will need to be removed by your veterinarian at a follow up appointment.

If infection was present antibiotics will be prescribed. Painkillers and anti-inflammatories will be prescribed as required.

Open drainage of a cyst allows for more complete drainage of fluid and tissue than withdrawal by a syringe, and is more effective at addressing the problem long-term. However, cysts are likely to recur even after being drained with an open drainage, and surgical removal is often required.

Your veterinarian may prescribe medications such as antibiotics, painkillers and anti- inflammatories to your cat after this procedure. Administer any medications as directed by your veterinarian. Pet owners will need to ensure that the area around the wound is clean and monitor the drain to ensure it does not become blocked. You will need to prevent your cat from licking or biting the drain or incision. An Elizabethan collar will be used to prevent your cat from interfering with the surgical site. You will need to restrict your cat's activity and cage rest may be necessary. Your veterinarian will make follow-up appointments to monitor the drain and determine when it can be removed.

If open drainage of a cyst is required it will cost between $200 and $400 for anesthetic, surgical procedure, medications and ½ day hospitalization. Costs may vary depending on the size and type of cyst being drained and your geographical region.

When performing a open drainage of a cyst there is a risk to your cat from the anesthetic used during the procedure. This can be mitigated by the availability of oxygen and medication to counteract any adverse reaction to an anesthetic by your cat. If infection is present, this also presents a risk to your cat's health. Open drainage of a cyst is usually performed to mitigate this risk and treatment with antibiotics provided to address infection.

Although not all cysts are avoidable, sebaceous cysts, caused by blockage in hair and epidermal follicles can be mitigated by ensuring your cat has a clean environment and assisting them with cleaning and bathing if required. Although cats usually take care of bathing themselves, some may need assistance from their owners with hygiene. By grooming your cat regularly you will be able to identify cysts at an early stage and receive intervention for them, if required, before they become problematic. Regular grooming also helps you to identify other health issues, and removes unwanted hair and dirt that will allow you to keep your home and your cat's environment more sanitary.